Daniel.

"So the record is mixed, but it has always been mixed. There have been moments when the United States was more influential than today and moments when it was less influential. The exertion of influence has always been a struggle, which may explain why, in every single decade since the end of World War II, Americans have worried about their declining influence and looked nervously as other powers seemed to be rising at their expense. The difficulties in shaping the international environment in any era are immense. Few powers even attempt it, and even the strongest rarely achieve all or even most of their goals. Foreign policy is like hitting a baseball: if you fail 70 percent of the time, you go to the Hall of Fame."